3of 4Fawns will beging hitting the ground in South Texas later this month Soaking rains across much of South Texas should trigger significant "green up," improving survival of fawns like the one carried by this very pregnant doe.Photo: Shannon Tompkins/Houston Chronicle

4of 4This week's expected rains will aid fawn survival by fueling a flush of vegetation growth that provides cover to hide newborns from predators and shield them from the effects of Texas' summer's often dangerously hot temperatures and dry conditions.Photo: Shannon Tompkins/Houston Chronicle

Later this month, whitetail fawns begin hitting the ground in much of the South Texas brush country in an annual mass birthing event that continues into mid-July.

What’s on that ground — specifically, what’s growing, has grown and will over the coming summer grow from that ground — plays a large role in determining how many of those fawns and the hundreds of thousands of other spotted newborns delivered earlier this spring and summer across this sprawling, ecologically diverse state see their first Thanksgiving.

That mostly is driven by what has fallen on that ground — rain, the fuel that powers so much of the engine of wildlife habitat.

As June reached its midpoint, the fuel gauge has been running way low in parts of South Texas and much of the rest of the state. The landscape reflects that.

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But that looks to possibly change over coming days, improving the odds for those fawns, their parents and many other wildlife species including quail, turkey and the state’s resident waterfowl. All — or almost all — could benefit from a good soaking.

“If we get the rain that’s predicted, it’ll certainly help in a lot of area. And it won’t help just deer,” Alan Cain, whitetail deer program leader for Texas Parks and Wildlife Department, said late last week of the rain that is forecast to fall on much of the state over the coming days.

After a stretch of three — four, in some regions — consecutive years of adequate, abundant and often way-too-abundant rainfall, Texas has hit a dry spell.

A year ago, barely 2 percent of the state was classified as suffering drought conditions, according to the National Drought Mitigation Center. The center’s most recent weekly report, issued June 12, rated 75 percent of the state as at least “abnormally dry.” Almost half of the state — 49.81 percent — was classified as undergoing drought with degrees ranging from moderate to exceptional.

Hardest hit regions are the Panhandle (where some spots have not seen measurable rain since lastautumn), western portions of the Edwards Plateau, portions of South Texas along the Rio Grande and the coastal plain from the mid-coast to the Rio Grande.

In a bit if cruel incongruity, even much of other upper Texas coast and East Texas, regions swamped with record rainfall and flooding a little more than nine months ago, are classified in “moderate” drought or “abnormally dry” drought.

Except in the crisp-and-getting crisper Panhandle and the Rolling Plains ecological region (where recent rains have significantly improved conditions), this dry period hasn’t been long-lived.

“We came through winter and through February and March in pretty good shape in most of the state, and we had a very cool spring,” Cain said.

Most wildlife came into spring in at least decent body condition. But the tap turned off in much of the state and by late April temperatures across the state climbed to unusually high levels. And the heat cranked up. May, usually one of the year’s wettest months, was one of the driest on record statewide.

In the hardest-hit areas, the grasses, forbs, shrubs and other low-growing, leafy vegetation so crucial to wildlife for cover and forage withered.

The impact of these conditions on wildlife so far has been fairly limited and isolated. But that is mostly because some areas have benefited from scattered showers and thunderstorms.

“In a lot of the state, it’s a patchwork quilt of range conditions,” said Cain, who has crisscrossed much of Texas over the past month or so. “You can see pockets where they got rain, and it’s green and things look great but drive five or 10 miles and everything’s brown.”

Those “brown” areas can be a problem for fawns. Grasses, forbs, shrubs and other low-growing, leafy vegetation crucial provide crucial camouflaging cover for newborn fawns, reducing predation. That abundance of forage also helps keep does in good body condition and able to nurse fawns.

But just as important, especially when temperatures are running much higher than normal as they have for the last month or more, is the cooling that cover offers the young deer.

“The biggest concern I have is not particularly how dry it is but how hot it is,” Cain said.

For the first few weeks of their lives, fawns spend all of their time curled motionless on the ground as their mother feeds, often far out of sight of the young deer. If that fawn doesn’t have overhead cover or is on open, bare ground, it not only is more vulnerable to predation but is subject to heat-related dangers.

Being exposed to 100- to 105-degree temperatures for long periods — and sometime does leave their carefully hidden fawns for several hours between visits for nursing — can led to dehydration and death.

“Without that cover, they can get overheated,” Cain said. “That can be fatal.”

Life is tough enough for fawns without the added stresses caused by poor habitat conditions and unusually hot temperatures. In a year with average to good habitat conditions, about 40 percent of fawns born in Texas survive their first six months. In poor years, survival can be half that or less. And drought years are the worst. In 2011, Texas endured its most severe single-year statewide drought. Many does in poor physical condition didn’t birth a fawn at all. Of fawns born that year, only about a quarter survived to autumn, and survival in regions hardest hit by drought were as low as 10 to 15 percent.

Fawn survival this year, as always, depends on how things play out over summer. And that depends in large part on rainfall.

But dry conditions — moderately dry conditions, not a full-blown drought — aren’t a great negative for Texas deer. After all, the state’s whitetails, like the vegetation that grows on Texas’ landscape, have evolved to survive the rainless, blistering hot sieges that are common occurrences. Both know how to take full advantage of rain when it does come.

And a dry spell actually can be welcomed. East Texas’ deer herd, for example, could use a spring and summer drier than the ones they have endured in recent years.

Heavy rains and resulting flooding during spring and summer of 2016 and 2017 and the biblical flooding associated with Hurricane Harvey last August and September caused loss of large numbers of fawns and even adult deer in portions of eastern Texas — mainly along the Trinity, Sabine, lower Colorado and Brazos. In some wide river basins where flooding inundated hundreds of thousands of acres of prime bottomland deer habitat, losses of fawns were devastating. Fawn survival in some pockets of East Texas was 25 percent or even lower, Cain said.

“There were multiyear losses of fawn crops in some areas associated with flooding,” Cain said.

The flooding also displaced surviving deer, making them more vulnerable. The result is a lower deer density and deer herd where some age classes are almost wholly absent.

A year or two of average fawn recruitment could quickly fill those holes. And conditions in much of East Texas, while drier than most would like to see them, remain relatively positive — at least for now. But a good rain certainly would be most welcomed. And its salubrious effects would be almost instant, especially in regions such as South Texas, where the plants and wildlife are designed to take full advantage of such opportunities.

“With rain, that country can turn from brown to green almost overnight,” Cain said.

But even if the rains forecast to come out of the Gulf and soak much of parched Texas aren’t the drought-breaker many hope them to be and the rest of summer turns out just as hot as it has begun, Texas’ deer herd, the largest in the nation, will remain stunningly healthy.

“Last year, we estimated we had 4.6 million whitetails, statewide,” Cain said. “Our deer herd is doing very well.”

Still, a good rain would be a fine way to welcome the next generation of whitetails to that group. For many, it could be a matter of life and death.

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